The present invention relates to a heat cooking apparatus, more specifically, to an improvement in a heat cooking apparatus employing a microprocessor for the purpose of controlling the heating of materials and a method of controlling same. A microwave oven is well known as an example of a heat cooking apparatus. Lately, microprocessors have been employed in such microwave ovens for the purpose of performing various cooking functions to achieve a simple circuit configuration with simple operator manipulation.
Conventionally, it is possible to control a heat cooking apparatus in response to the temperature of materials being cooked, as shown, for example, in U.S. Pat. Nos. 4,347,418 and 4,383,157. For such cooking apparatus, a temperature measuring means is employed, as, for example, an infrared radiation detecting device. The microprocessor controls the heat cooking operation to deenergize the heating apparatus and to adjust the output of the heating energy during operation thereof in response to a signal from the temperature measuring means. The temperature measuring means (sensor) is very sensitive, and may malfunction in use resulting from steam in the cooking apparatus. When the cooking apparatus does not de-energize and stop the cooking operation in response to sensed temperature because of a defect in the sensor, the heating is nevertheless terminated at a default time provided as a safety back-up, as shown, for example, in Japanese Pat. No. 57-42817 published on Sept. 10, 1982.
However, a disadvantage in this apparatus is encountered since the user cannot determine whether the heating was forcibly stoppped due to a malfunctioning sensor or stopped normally in response to the food products reaching the correct temperature. Namely, when heat cooking is forcibly terminated, a user may think that the heat cooking apparatus simply does not cook very well, and not recognize that the sensor is dirty and needs cleaning.